Techniques & Technologies

Glasses

Choosing spectacle frames.

Glasses, or spectacles, correct vision. Glass, and now plastic, lenses, shaped to compensate for sight impairments, are held in front of the eyes by a frame.

Glass or crystal lenses to assist vision evolved from magnifying glasses, known as reading stones. The English monk Roger Bacon was one of the first to be associated with the development of glasses. Around 1268 he published a work outlining the scientific principles behind corrective lenses. Two years later, merchant-explorer Marco Polo claimed he saw elderly men wearing spectacles while he was travelling through China. Chinese historians believe these devices came to China from Arabia in the late 1000s.

Glasses as we recognise them appeared in the 1700s. Spectacle frames held over the ears were designed in 1727 by British optician Edward Scarlett, though his designs were not immediately successful. Other styles of spectacles were fashionable well into the 1800s. These included scissors-glasses and lorgnettes, lenses held by handles. Glasses held in place by a mechanism pinching the nose were called pince-nez.

Glasses with two types of lenses are called bifocals. These were developed in 1784 by American scientist Benjamin Franklin, who suffered from long and short vision. He invented bifocals to avoid switching between two pairs of glasses.

Correcting sight was a national issue in 20th-century Britain. First World War troops were given glasses to help them fight. Spectacles were made freely available to all after the National Health Service was created in 1948. Glasses are now part of personal image and expression.